Other World Computing reports that the iMac EFI Update 1.6 released yesterday for Apple's new iMacs brings an unadvertised improvement in SATA performance for the internal hard drive bays.
While iMac EFI Update 1.6 is described as including "fixes that improve performance and stability for Thunderbolt," it would also seem that an unadvertised benefit is that it also unlocks the full 6Gb/s, SATA 3.0 capabilities of two of the internal drive bays.
Unfortunately, the optical bay remains at 3Gb/s.
The report notes that Apple also released an EFI update for the current MacBook Pros yesterday, but it is unclear whether that update attempts to address SATA performance issues found in the 17-inch models.
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Top Rated Comments
The Z68 chipset has provisions for 6 SATA ports, 2x 6GB/s, 4x 3GB/s. Its the reason why motherboard manufacturers include marvell and other SATA chips to offer more than the 2x 6GB/s ports you would get relying solely on the Intel chipset.
If you install a drive that cannot make use of the temperature sensor that the drive you took out did, then yes, the fan will run at full speed. I took out my optical drive and upgraded my iMac to SSD + HDD and now my optical drive fan runs at max speed - UNLESS I tell it otherwise with SMC Fan Control, which is a free utility you can download :p so... I have no problems.
This is unsupported, therefore irrelevant for the purposes of this update...what really matters is that internal SSDs would benefit from it...EXCELLENT news that should silence the whining of some people around here.
GO APPLE!
Some people remove the optical drive and use it as a hard drive bay.
What the hell? No optical drive can reach 3GB/s